Flaxseed inhibits metastasis and decreases extracellular vascular endothelial growth factor in human breast cancer xenografts.

Key Findings:

Vascular endothelial growth factor (VEGF) is a key factor in promotion of tumor angiogenesis and in breast cancer VEGF mRNA expression is increased compared to adjacent normal breast tissue. MDAMB- 435 tumors produce distant metastases in 80– 100% of recipients and is a tool for analysis of the cellular and molecular basis of the metastasis of advanced breast cancer. Here flaxseed fed to nude mice with established MDA-MB-435 tumor explants affected tumor growth, metastasis, and extracellular VEGF. In a previous study, 10% FS inhibited breast cancer growth and metastasis by down regulation of expression of insulin growth factor-1 and epidermal growth factor receptor. The present study suggests that the slow tumor growth rate seen in the mice after a FS diet may be attributed to its effect on tumor angiogenesis.  FS given to nude mice with established human breast cancer xenografts reduced the tumor growth rate and the development of distant metastasis.

ABSTRACT:

Angiogenesis is important in tumor growth, progression and metastatic dissemination. Vascular endothelial growth factor (VEGF) is one key factor in promotion of breast cancer angiogenesis. VEGFs are bioactive in the extracellular space where they become available to the endothelial cells. Phytoestrogens such as lignans have been shown to alter breast cancer incidence and be cancer-protective in rats. We show that supplementation of 10% flaxseed, the richest source of mammalian lignans, to nude mice with established human breast tumors reduced tumor growth and metastasis. Moreover, flaxseed decreased extracellular levels of VEGF, which may be one mechanistic explanation to the decreased tumor growth and metastasis